Methods and systems for displaying a vertical profile for an aircraft procedure with nonuniform scaling

ABSTRACT

Methods and systems are provided for presenting procedure information for a vertical profile on a display device associated with an aircraft. A method comprises displaying a first segment of the plurality of segments comprising a vertical profile with a first vertical scale and a first horizontal scale, wherein the first horizontal scale is based on a first distance associated with the first segment. The method further comprises displaying a second segment of the plurality of segments with the first vertical scale and a second horizontal scale, wherein the second horizontal scale is based on a second distance associated with the second segment. The first horizontal scale and the second horizontal scale are not equal. In this manner, the vertical profile has a nonuniform horizontal scale and a uniform vertical scale across segments.

TECHNICAL FIELD

The subject matter described herein relates generally to avionicssystems, and more particularly, embodiments of the subject matter relateto avionics systems and related cockpit displays adapted for displayinga vertical profile for an aircraft action such as an instrumentapproach.

BACKGROUND

Instrument procedures (e.g., instrument approach procedures orinstrument departure procedures) are used to provide specific detailedinstructions for the operation of aircraft in the airport terminal area,and allows air traffic control to reduce radio frequency congestion bycommunicating only the name of the procedure to be flown, rather thanhaving to provide the verbose instructions otherwise required. Forexample, instrument approach procedures allow a pilot to reliably landan aircraft in situations of reduced visibility or inclement weather byusing instruments onboard the aircraft or on the ground, such as radiosor other communication systems, navigation systems, localizers,glidescopes, and the like. Published aeronautical charts, such as, forexample, Instrument Approach Procedure (IAP) charts, Standard TerminalArrival (STAR) charts, or Terminal Arrival Area (TAA) charts StandardInstrument Departure (SID) routes, Departure Procedures (DP), terminalprocedures, approach plates, and the like, that depict and describe theinstrument procedures for various airports, runways, or other landingand/or departure locations are provided by a governmental or regulatoryorganization, such as, for example, the Federal Aviation Administrationin the United States. These charts graphically illustrate and describethe specific procedures (e.g., minimum descent altitudes, minimum runwayvisual range, final course or heading, relevant radio frequencies,missed approach procedures) to be followed or otherwise utilized by apilot for a particular approach or departure. A pilot maintains copiesof these printed charts for the various possible airports that the pilotmay encounter during operation of the aircraft. For example, forworldwide operation, there are as many as 17,000 charts, and eachairport may include multiple runways with multiple possible approachesand departures.

Typically, in advance of the actual approach or departure, the pilotidentifies the airport and reviews the charts for the one or moreapproaches (or departures) for that airport. Once the pilot determinesthe approach (or departure) that the pilot intends to fly, the pilot andcrew (e.g., the co-pilot) review features of the instrument proceduresuch that there is sufficient understanding and agreement on how theprocedure should be executed based on the chart. These printed chartscontain a significant amount of information making it difficult todisplay them in their entirety electronically onboard the aircraft. Forexample, in current electronic cockpit displays, the resolution andphysical size of the electronic display limits or prevents theinstrument procedure charts to be reproduced or replicatedelectronically. Furthermore, most of the display area on the electronicdisplay is already utilized or reserved for other processes (e.g.,navigational maps, profile views, synthetic vision displays, flightmanagement windows, and the like) and presenting the instrumentprocedure chart risks interfering with or obfuscating these otherprocesses.

Instrument approach plates include a vertical profile for a desiredapproach that consists of a series of navigational segments withconstraining altitudes (e.g., minimum descent altitudes) and additionalgraphical and textual information corresponding to the various stages ofthe approach and/or departure. Often, the published vertical profilesare unscaled in both the horizontal and vertical dimensions. However,placing aircraft symbology and/or the terrain on a vertical profile thatlacks a fixed vertical scale is misleading to the pilot. In addition,the navigational segments vary greatly in size, some being only a halfmile or less while others may be ten or more miles long. Therefore,given the limited display area allocated to the vertical profile,attempting to display the navigational segments with a fixed scalecauses some smaller navigational segments to be imperceptibly small andcreates difficulty in displaying the necessary text between waypointsfor the navigational segment, while some larger navigational segmentsrequire an unwieldy amount of the display area.

BRIEF SUMMARY

A method is provided for presenting procedure information for a verticalprofile on a display device associated with an aircraft. The verticalprofile comprises a plurality of segments between a first navigationalreference point and a second navigational reference point. The methodcomprises displaying a first segment of the plurality of segments with afirst vertical scale and a first horizontal scale, wherein the firsthorizontal scale is based on a first distance associated with the firstsegment. The method further comprises displaying a second segment of theplurality of segments with the first vertical scale and a secondhorizontal scale, wherein the second horizontal scale is based on asecond distance associated with the second segment. In an exemplaryembodiment, the first horizontal scale and the second horizontal scaleare not equal.

In another embodiment, a method is provided for presenting procedureinformation for an aircraft action between a first navigationalreference point and a second navigational reference point on a displaydevice associated with an aircraft. The method comprises rendering avertical profile for the aircraft action on the display device with auniform vertical scale and a nonuniform horizontal scale, and renderinga graphical representation of terrain on the display device within thevertical profile. The graphical representation of terrain is renderedbased on the uniform vertical scale and the nonuniform horizontal scale.

This summary is provided to introduce a selection of concepts in asimplified form that are further described below in the detaileddescription. This summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used as an aid in determining the scope of the claimed subjectmatter.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the subject matter will hereinafter be described inconjunction with the following drawing figures, wherein like numeralsdenote like elements, and

FIG. 1 is a block diagram of a display system suitable for use in anaircraft in accordance with one embodiment;

FIG. 2 is a flow diagram of an exemplary aircraft procedure displayprocess suitable for use with the display system of FIG. 1 in accordancewith one embodiment;

FIG. 3 is a schematic view of an exemplary navigational map including avertical profile suitable for use with the aircraft procedure displayprocess of FIG. 2 in accordance with one embodiment; and

FIG. 4 is a schematic view of an exemplary navigational map including avertical profile suitable for use with the aircraft procedure displayprocess of FIG. 2 in accordance with one embodiment.

DETAILED DESCRIPTION

The following detailed description is merely exemplary in nature and isnot intended to limit the subject matter of the application and usesthereof. Furthermore, there is no intention to be bound by any theorypresented in the preceding background or the following detaileddescription.

Techniques and technologies may be described herein in terms offunctional and/or logical block components, and with reference tosymbolic representations of operations, processing tasks, and functionsthat may be performed by various computing components or devices. Itshould be appreciated that the various block components shown in thefigures may be realized by any number of hardware, software, and/orfirmware components configured to perform the specified functions. Forexample, an embodiment of a system or a component may employ variousintegrated circuit components, e.g., memory elements, digital signalprocessing elements, logic elements, look-up tables, or the like, whichmay carry out a variety of functions under the control of one or moremicroprocessors or other control devices.

The following description refers to elements or nodes or features being“coupled” together. As used herein, unless expressly stated otherwise,“coupled” means that one element/node/feature is directly or indirectlyjoined to (or directly or indirectly communicates with) anotherelement/node/feature, and not necessarily mechanically. Thus, althoughthe drawings may depict one exemplary arrangement of elements,additional intervening elements, devices, features, or components may bepresent in an embodiment of the depicted subject matter. In addition,certain terminology may also be used in the following description forthe purpose of reference only, and thus are not intended to be limiting.

For the sake of brevity, conventional techniques related to graphics andimage processing, navigation, flight planning, aircraft controls, andother functional aspects of the systems (and the individual operatingcomponents of the systems) may not be described in detail herein.Furthermore, the connecting lines shown in the various figures containedherein are intended to represent exemplary functional relationshipsand/or physical couplings between the various elements. It should benoted that many alternative or additional functional relationships orphysical connections may be present in an embodiment of the subjectmatter.

Technologies and concepts discussed herein relate to display systemsadapted for displaying, on a display device associated with an aircraft,a vertical profile for an aircraft action such as an instrumentapproach. The vertical profile is displayed and/or rendered with a fixeduniform vertical scale and a nonuniform horizontal scale. This allowsthe entire vertical profile to be displayed and/or rendered within alimited amount of display area on the display device, while accuratelyrepresenting the position of the aircraft with respect to the underlyingterrain and the approach course. As a result, the desired and/orrelevant instrument procedure information may thereby be concurrentlypresented on the same display device as the navigational map in a mannerthat does not degrade the situational awareness provided by thenavigational map while improving the situational awareness regarding theexecution of the approach.

FIG. 1 depicts an exemplary embodiment of a display system 100, whichmay be located onboard an aircraft 118. In an exemplary embodiment, thedisplay system 100 includes, without limitation, a display device 102, anavigation system 104, a communications system 106, a flight managementsystem 108 (FMS), a processing architecture 112, and a graphics module114. The display system 100 may further include a user interface 110 forenabling interactivity with the display system 100 and a database 116suitably configured to support operation of the display system 100, asdescribed in greater detail below. It should be understood that FIG. 1is a simplified representation of a display system 100 for purposes ofexplanation and ease of description, and FIG. 1 is not intended to limitthe application or scope of the subject matter in any way. In practice,the display system 100 and/or aircraft 118 will include numerous otherdevices and components for providing additional functions and features,as will be appreciated in the art.

In an exemplary embodiment, the display device 102 is coupled to thegraphics module 114. The graphics module 114 is coupled to theprocessing architecture 112, and the processing architecture 112 and thegraphics module 114 are cooperatively configured to display, render, orotherwise convey one or more graphical representations or imagesassociated with operation of the aircraft 118 on the display device 102,as described in greater detail below. The processing architecture 112 iscoupled to the navigation system 104 for obtaining real-timenavigational data and/or information regarding operation of the aircraft118 to support operation of the display system 100. In an exemplaryembodiment, the communications system 106 is coupled to the processingarchitecture 112 and configured to support communications to and/or fromthe aircraft 118, as will be appreciated in the art and described ingreater detail below. The processing architecture 112 is also coupled tothe flight management system 108, which in turn, may also be coupled tothe navigation system 104 and the communications system 106 forproviding real-time data and/or information regarding operation of theaircraft 118 to the processing architecture 112 to support operation ofthe aircraft 118, as will be appreciated in the art. In an exemplaryembodiment, the user interface 110 is coupled to the processingarchitecture 112, and the user interface 110 and the processingarchitecture 112 are cooperatively configured to allow a user tointeract with the display device 102 and other elements of displaysystem 100, as described in greater detail below.

In an exemplary embodiment, the display device 102 is realized as anelectronic display configured to graphically display flight informationor other data associated with operation of the aircraft 118 undercontrol of the graphics module 114. In an exemplary embodiment, thedisplay device 102 is located within a cockpit of the aircraft 118. Itwill be appreciated that although FIG. 1 shows a single display device102, in practice, additional display devices may be present onboard theaircraft 118. In an exemplary embodiment, the user interface 110 is alsolocated within the cockpit of the aircraft 118 and adapted to allow auser (e.g., pilot, co-pilot, or crew member) to interact with thedisplay system 100 and enables a user to indicate, select, or otherwisemanipulate content displayed on the display device 102, as described ingreater detail below. In various embodiments, the user interface 110 maybe realized as a keypad, touchpad, keyboard, mouse, touchscreen,joystick, microphone, or another suitable device adapted to receiveinput from a user. It should be appreciated that although FIG. 1 showsthe display device 102 and the user interface 110 as being locatedwithin the aircraft 118, in practice, the display device 102 and/or userinterface 110 may be located outside the aircraft 118 (e.g., on theground as part of an air traffic control center or another commandcenter) and communicatively coupled to the remaining elements of thedisplay system 100 (e.g., via a data link).

In an exemplary embodiment, the navigation system 104 is configured toobtain one or more navigational parameters associated with operation ofthe aircraft 118. The navigation system 104 may be realized as a globalpositioning system (GPS), inertial reference system (IRS), or aradio-based navigation system (e.g., VHF omni-directional radio range(VOR) or long range aid to navigation (LORAN)), and may include one ormore navigational radios or other sensors suitably configured to supportoperation of the navigation system 104, as will be appreciated in theart. In an exemplary embodiment, the navigation system 104 is capable ofobtaining and/or determining the instantaneous position of the aircraft118, that is, the current location of the aircraft 118 (e.g., thelatitude and longitude) and the altitude or above ground level for theaircraft 118. In some embodiments, the navigation system 104 may alsoobtain and/or determine the heading of the aircraft 118 (i.e., thedirection the aircraft is traveling in relative to some reference).

In an exemplary embodiment, the communications system 106 is suitablyconfigured to support communications between the aircraft 118 andanother aircraft or ground location (e.g., air traffic control). In thisregard, the communications system 106 may be realized using a radiocommunication system or another suitable data link system. In anexemplary embodiment, the flight management system 108 (or,alternatively, a flight management computer) is located onboard theaircraft 118. Although FIG. 1 is a simplified representation of displaysystem 100, in practice, the flight management system 108 may be coupledto one or more additional modules or components as necessary to supportnavigation, flight planning, and other aircraft control functions in aconventional manner.

In accordance with one or more embodiments, the flight management system108 includes or otherwise accesses a database that contains procedureinformation for a plurality of airports. As used herein, procedureinformation should be understood as a set of operating parameters orinstructions associated with a particular aircraft action (e.g., landingand/or approach, take off and/or departure, taxiing) that may beundertaken by the aircraft 118 at a particular airport. In this regard,an airport should be understood as referring to a location suitable forlanding (or arrival) and/or takeoff (or departure) of an aircraft, suchas, for example, airports, runways, landing strips, and other suitablelanding and/or departure locations. In an exemplary embodiment, theflight management system 108 maintains the association of the procedureinformation and the corresponding airport. In an exemplary embodiment,the procedure information maintained by the flight management system 108(e.g., in a database) comprises instrument procedure informationtraditionally displayed on a published chart (or approach plate) for theairport, as will be appreciated in the art. In this regard, theprocedure information may comprise instrument approach procedures,standard terminal arrival routes, instrument departure procedures,standard instrument departure routes, obstacle departure procedures, orother suitable instrument procedure information. It should beappreciated that although the subject matter may described herein in thecontext of an instrument approach procedure for purposes of explanation,the subject matter is not intended to be limited to an approachprocedure, and in practice, the subject matter may be implemented fordepartures and other aircraft actions in a similar manner as describedbelow.

Each airport (or landing location) may have one or more predefinedapproaches associated therewith, wherein each approach may haveinstrument approach procedure information associated therewith. Forexample, an airport may comprise a plurality of possible approachesdepending on the particular airport runway chosen for landing. In thisregard, the flight management system 108 maintains the association ofthe instrument approach procedure information and the correspondingapproach for each airport or landing location. In a similar manner, anairport (or departure location) may have at least one departure routehaving instrument departure procedure information associated therewith,as will be appreciated in the art. In an exemplary embodiment, theflight management system 108, the processing architecture 112 and thegraphics module 114 are cooperatively configured to render and/ordisplay instrument approach procedure information for an identifiedapproach (or instrument departure procedure information for anidentified departure route) on the display device 102, as described ingreater detail below.

The processing architecture 112 generally represents the hardware,software, and/or firmware components configured to facilitate thedisplay and/or rendering of instrument procedure information on thedisplay device 102 and perform additional tasks and/or functionsdescribed in greater detail below. Depending on the embodiment, theprocessing architecture 112 may be implemented or realized with ageneral purpose processor, a content addressable memory, a digitalsignal processor, an application specific integrated circuit, a fieldprogrammable gate array, any suitable programmable logic device,discrete gate or transistor logic, discrete hardware components, or anycombination thereof, designed to perform the functions described herein.The processing architecture 112 may also be implemented as a combinationof computing devices, e.g., a combination of a digital signal processorand a microprocessor, a plurality of microprocessors, one or moremicroprocessors in conjunction with a digital signal processor core, orany other such configuration. In practice, the processing architecture112 includes processing logic that may be configured to carry out thefunctions, techniques, and processing tasks associated with theoperation of the display system 100, as described in greater detailbelow. Furthermore, the steps of a method or algorithm described inconnection with the embodiments disclosed herein may be embodieddirectly in hardware, in firmware, in a software module executed by theprocessing architecture 112, or in any practical combination thereof.

The graphics module 114 generally represents the hardware, software,and/or firmware components configured to control the display and/orrendering of instrument procedure information on the display device 102and perform additional tasks and/or functions described in greaterdetail below. In an exemplary embodiment, the graphics module 114accesses one or more databases 116 suitably configured to supportoperations of the graphics module 114, as described below. In thisregard, the database 116 may comprise a terrain database, an obstacledatabase, a navigational database, a geopolitical database, or otherinformation for rendering and/or displaying content related to aninstrument approach procedure on the display device 102, as describedbelow.

Referring now to FIG. 2, in an exemplary embodiment, a display system100 may be configured to perform an aircraft procedure display process200 and additional tasks, functions, and operations described below. Thevarious tasks may be performed by software, hardware, firmware, or anycombination thereof. For illustrative purposes, the followingdescription may refer to elements mentioned above in connection withFIG. 1. In practice, the tasks, functions, and operations may beperformed by different elements of the described system, such as thedisplay device 102, the navigation system 104, the communications system106, the flight management system 108, the user interface 110, theprocessing architecture 112, the graphics module 114 and/or the database116. It should be appreciated that any number of additional oralternative tasks may be included, and may be incorporated into a morecomprehensive procedure or process having additional functionality notdescribed in detail herein.

Referring again to FIG. 2, and with continued reference to FIG. 1, anaircraft procedure display process 200 may be performed present aircraftprocedure information (e.g., an instrument approach procedure orinstrument departure procedure) for a desired aircraft action (e.g., anapproach or a departure) at an airport on a display device in order toenable a user, such as a pilot or crew member, to review and/or briefthe procedure without reliance on paper charts. It should be appreciatedthat although the aircraft procedure display process 200 is described inthe context of an approach (or instrument approach procedure) forpurposes of explanation, the aircraft procedure display process 200 maybe implemented for instrument departure procedures and other proceduresin a similar manner as described herein.

In an exemplary embodiment, the aircraft procedure display process 200initializes by displaying a navigational map relating to operation of anaircraft on a display device associated with the aircraft (task 202).For example, referring now to FIG. 3, and with continued reference toFIG. 1 and FIG. 2, the aircraft procedure display process 200 maydisplay and/or render a navigational map 300 associated with a current(or instantaneous) location of an aircraft on a display device in theaircraft. In this regard, the graphics module 114 may be configured tocontrol the rendering of the navigational map 300, which may begraphically displayed on the display device 102. The aircraft proceduredisplay process 200 may also be configured to render a graphicalrepresentation of the aircraft 302 on the map 300, which may be overlaidor rendered on top of a background 304. In an exemplary embodiment, thebackground 304 comprises a graphical representation of the terrain,topology, or other suitable items or points of interest corresponding to(or within a given distance of) a location of the aircraft 118, whichmay be maintained in a terrain database, a navigational database, ageopolitical database, or another suitable database. As described ingreater detail below, the aircraft procedure display process 200 mayalso render a graphical representation of an airport 306 overlying thebackground 304. It should be appreciated that although the subjectmatter may be described herein in the context of a navigational map, thesubject matter is not intended to be limited to a particular type ofcontent displayed on the display device and the aircraft proceduredisplay process 200 may be implemented with other types of content, suchas, for example, an airport map or terminal map.

Although FIG. 3 depicts a top view (e.g., from above the aircraft 302)of the navigational map 300, in practice, alternative embodiments mayutilize various perspective views, such as three-dimensional views(e.g., a three-dimensional synthetic vision display), angular or skewedviews, and the like. Further, depending on the embodiment, the aircraft302 may be shown as traveling across the map 300, or alternatively, asbeing located at a fixed position on the map 300, and FIG. 3 is notintended to limit the scope of the subject matter in any way. In anexemplary embodiment, the map 300 is associated with the movement of theaircraft, and the background 304 refreshes or updates as the aircrafttravels, such that the graphical representation of the aircraft 302 ispositioned over the terrain background 304 in a manner that accuratelyreflects the current (e.g., instantaneous or substantially real-time)real-world positioning of the aircraft 118 relative to the earth. Inaccordance with one embodiment, the map 300 is updated or refreshed suchthat it is centered on and/or aligned with the aircraft 302. Dependingon the embodiment, the navigational map 300 may be oriented north-up(i.e., moving upward on the map 300 corresponds to traveling northward)or track-up or heading-up (i.e., aligned such that the aircraft 302 isalways traveling in an upward direction and the background 304 adjustedaccordingly), as will be appreciated in the art.

In an exemplary embodiment, the aircraft procedure display process 200continues by identifying a desired airport (e.g., a landing and/ordeparture location) for the aircraft (task 204). In this regard, anairport may comprise a runway, a landing strip, an airstrip, or anothersuitable landing and/or departure location that has aircraft procedureinformation (e.g., instrument approach procedures or instrumentdeparture procedures) associated therewith. In accordance with oneembodiment, the aircraft procedure display process 200 may identify thedesired airport using the navigational map 300 displayed on the displaydevice 102. For example, as shown in FIG. 3, the aircraft proceduredisplay process 200 may display an airport 306 proximate the aircraft118 overlying the background 304 on the navigational map 300. Theaircraft procedure display process 200 may identify the desired airportin response to a user selecting or indicating an airport displayed onthe display device. For example, a user may manipulate the userinterface 110 and indicate or otherwise select the airport 306 displayedon the map 300 as the desired airport (e.g., by positioning a cursor orpointer over airport 306 and clicking or otherwise selecting airport306). In another embodiment, the aircraft procedure display process 200may identify the desired airport using a predetermined (or predefined)flight plan. For example, the flight management system 108 may maintaina flight plan that specifies airport 306 as the final entry (ordestination) of the flight plan.

In an exemplary embodiment, the aircraft procedure display process 200continues by identifying a desired aircraft action for the identifiedairport, wherein the identified action has procedure informationassociated therewith (task 206). In this regard, an aircraft actionshould be understood as referring to an approach (or landing), adeparture (or takeoff), taxiing, or another aircraft action havingprocedure information associated with the particular action. Forexample, in accordance with one embodiment, the aircraft proceduredisplay process 200 may identify a desired approach for the identifiedairport. As used herein, an approach should be understood as referringto a predefined flight path or other guidance intended to facilitate asafe landing for an aircraft at a particular runway, landing strip,airstrip, or another suitable landing location. If the identifiedairport has only a single approach associated therewith (e.g., theairport is an airstrip or comprises a single runway), the aircraftprocedure display process 200 may identify that approach as the desiredapproach. In accordance with one embodiment, if the identified aircrafthas a plurality of possible approaches (e.g., the airport comprises aplurality of runways), the aircraft procedure display process 200 mayidentify or otherwise determine a default approach for use as a desiredapproach for the airport. For example, the aircraft procedure displayprocess 200 may identify the most commonly used approach for theidentified airport 306 as the default approach. Alternatively, theaircraft procedure display process 200 may identify the most recentlyused approach as the desired approach. In another embodiment, theaircraft procedure display process 200 determines and/or identifies thedesired approach based on the current heading and/or location of theaircraft 118. For example, the aircraft procedure display process 200may identify the approach with a final approach course most closelyaligned with the current heading of the aircraft 118 as the desiredapproach. In yet another embodiment, the aircraft procedure displayprocess 200 may identify or otherwise determine the desired approachbased on an input from a user via user interface 110. As shown in FIG.3, in response to identifying the desired approach for the airport 306,the aircraft procedure display process 200 may render and/or display agraphical representation of the approach course 307 on the navigationalmap 300.

As described in greater detail below, in response to identifying theaircraft action for the airport, the aircraft procedure display process200 continues by displaying and/or rendering a vertical profileassociated with the identified aircraft action based on the instrumentprocedure information for the identified aircraft action. Depending onthe embodiment, the vertical profile may be rendered and/or displayedoverlying the content displayed on the display device or adjacent to thecontent displayed on the display device. For example, as shown in FIG.3, the vertical profile 308 may be rendered and/or displayed overlyingthe bottom (or lower) portion of the navigational map 300. It should beappreciated that in other embodiments, the vertical profile 308 may berendered and/or displayed overlying (or adjacent to) the top (or upper)portion of the displayed content (e.g., navigational map 300), and thesubject matter is not intended to be limited to any particulararrangement of the vertical profile with respect to other displayedcontent.

In an exemplary embodiment, the vertical profile is displayed and/orrendered with a uniform vertical scale and a nonuniform horizontalscale, as described in greater detail below. As used herein, a uniformvertical scale (or alternatively, a linear vertical scale) should beunderstood as a property and/or characteristic of the vertical profilesuch that the ratio of a vertical unit of distance on the display device(e.g., one pixel vertically) corresponds to the same real-world verticaldistance (e.g., altitude) relative to a reference level (e.g., groundlevel or mean sea level) for any location within the vertical profile.As used herein, a nonuniform horizontal scale (or alternatively, anonlinear horizontal scale) should be understood as a property and/orcharacteristic of the vertical profile such that the ratio of ahorizontal unit of distance on the display device (e.g., one pixelhorizontally) corresponds to a different real-world horizontal distancedepending on the segment within the vertical profile.

In an exemplary embodiment, the vertical profile for the identifiedaircraft action comprises a plurality of segments, wherein each segmentof the plurality of segments is associated with particular instrumentapproach procedure information pertaining to operating the aircraftwithin the region corresponding to the respective segment. For example,as shown in FIG. 3, the vertical profile 308 for the identified approachto the airport 306 comprises a plurality of navigational segments 310,312, 314, 316 from a first navigational reference point 311 (e.g., aninitial approach fix labeled as RNO44) to the landing location 306. Inthe illustrated embodiment, the first navigational segment 310corresponds to a portion of the approach from the first navigationalreference point 311 to a second navigational reference point 313 (e.g.,labeled as TAKLE), the second navigational segment 312 corresponds to aportion of the approach from the second navigational reference point 313to a third reference point 315 (e.g., labeled as DICEY), the thirdnavigational segment 314 corresponds to a portion of the approach fromthe third reference point 315 to a fourth reference point 317 (e.g.,labeled as I16RM), and the fourth navigational segment 316 correspondsto a portion of the approach from the fourth reference point 317 to thelanding location 306. Depending on the particular approach and/orairport, the navigational reference points may comprise navigationalaids, such as VHF omni-directional ranges (VORs), distance measuringequipment (DMEs), tactical air navigation aids (TACANs), andcombinations thereof (e.g., VORTACs), the landing and/or departurelocation (e.g., the runway) or other features on the ground, as well asposition fixes (e.g., initial approach fixes (IAFs) and/or finalapproach fixes (FAFs)) and other navigational reference points used inarea navigation (RNAV). As described in greater detail below, eachsegment of the plurality of navigational segments 310, 312, 314, 316 hasan associated distance equal to the straight-line ground distancebetween the two navigational reference points that define thenavigational segment. In addition, the navigational segments may alsohave altitude criteria (e.g., minimum descent altitudes) and additionalinstrument procedure information and/or criteria associated therewith.In addition, the vertical profile 308 may also comprise a runway segment318 as well as a pre-approach segment 320, as described in greaterdetail below.

In an exemplary embodiment, the aircraft procedure display process 200displays and/or renders the vertical profile by determining displaydimensions for the vertical profile (task 208). In this regard, theaircraft procedure display process 200 determines the available area onthe display device that will be dedicated and/or allocated to thevertical profile. For example, the display device may have apredetermined viewing area comprising a plurality of pixels (or imageelements) arranged in a two-dimensional grid or matrix, wherein thedisplay device has a fixed vertical resolution (e.g., a fixed number ofhorizontal rows of pixels) and a fixed horizontal resolution (e.g., afixed number of vertical columns of pixels). The aircraft proceduredisplay process 200 may determine display dimensions for the verticalprofile by determining the number of rows of pixels (the verticaldisplay dimension) on the display device to be dedicated and/orallocated to the vertical profile along with the number of columns ofpixels (the horizontal display dimension) on the display device thatwill be dedicated and/or allocated to the vertical profile. Inaccordance with one or more embodiments, the display dimensions for thevertical profile may be determined as a percentage of the viewing area.For example, the vertical display dimension for the vertical profile maybe determined as a percentage of the vertical resolution of the displaydevice (e.g., fifteen percent of the total number of rows of pixels) andthe horizontal display dimension for the vertical profile may bedetermined as a percentage of the horizontal resolution of the displaydevice. As shown in FIG. 3, in an exemplary embodiment, the horizontaldisplay dimension for the vertical profile 308 is equal to one hundredpercent of the horizontal resolution of the viewing area of the displaydevice, that is, the entire width of the viewing area. The verticaldisplay dimension of the vertical profile 308 is constrained by thenavigational map 300 which occupies a majority of the vertical dimensionof the viewing area.

After determining the display dimensions for the vertical profile, theaircraft procedure display process 200 continues by allocating thedisplay dimensions of the vertical profile among the segments thatcomprise the vertical profile (task 210). In this regard, the aircraftprocedure display process 200 may allocate, to each segment, horizontaldimensions (e.g., a number of columns of pixels) and vertical dimensions(e.g., a number of rows of pixels) that comprise a subset of the displaydimensions for the vertical profile. Preferably, the aircraft proceduredisplay process 200 allocates sufficient dimensions to the segments suchthat the dimension of each segment allows the aircraft procedure displayprocess 200 to adequately display and/or convey the instrument procedureinformation associated with the respective segment within the respectivesegment. In an exemplary embodiment, the aircraft procedure displayprocess 200 allocates the same vertical dimensions to each segment, suchthat, for example, each segment comprises the same number of rows ofpixels resulting in a vertical profile of uniform vertical dimension.The aircraft procedure display process 200 continues by allocatinghorizontal dimensions to the individual segments, and depending on theembodiment, the horizontal dimensions of the segments may or may not beuniform. For example, the aircraft procedure display process 200 mayallocate a first number of columns of pixels to the first segment 310and a second number of columns of pixels to the second segment 312. Inaccordance with one embodiment, the navigational segments are allocatedhorizontal dimensions in a piecewise linear fashion as shown in FIG. 3,that is, each navigational segment 310, 312, 314, 316 is allocated thesame number of columns of pixels. In alternative embodiments, thenavigational segments may be allocated horizontal dimensionsnon-uniformly, that is, a first navigational segment may be allocated afirst number of columns of pixels and a second navigational segment maybe allocated a different number of columns of pixels. In a similarmanner, the aircraft procedure display process 200 may allocatehorizontal dimensions to the other segments 318, 320 that are the sameas and/or different from those allocated to the navigational segments310, 312, 314, 316.

In an exemplary embodiment, the aircraft procedure display process 200continues by determining the uniform vertical scale for the segments ofthe vertical profile based on the allocated display dimensions (task212). As used herein, the vertical scale should be understood as theratio of a vertical unit of distance on the display device (e.g., movingone pixel vertically or one row of pixels) to the equivalent real-worldvertical distance (e.g., altitude) relative to a reference level (e.g.,ground level or mean sea level). The vertical scale is the same for eachsegment of the vertical profile, such that the vertical profile isdisplayed with a uniform vertical scale. In accordance with embodiment,the aircraft procedure display process 200 determines the vertical scalefor the navigational segments of the vertical profile based on thehighest altitude minimum among the plurality of segments that comprisethe vertical profile. The aircraft procedure display process 200 mayidentify the segment having the highest altitude minimum, and determinethe vertical scale based on the altitude minimum associated with theidentified segment. For example, as shown in FIG. 3, the pre-approachsegment 320 has the highest altitude minimum (e.g., 9,000 ft) among theplurality of segments 310, 312, 314, 316, 318, 320. The aircraftprocedure display process 200 may determine the vertical scale based ondifference between the altitude minimum for the segment 320 and thelowest reference level for the vertical profile 308 (e.g., the elevationof the airport 306). Preferably, the aircraft procedure display process200 determines the uniform vertical scale as a ratio of a number of rowsof pixels to the difference between the highest altitude minimum and thelowest reference level for the vertical profile in a manner thataccounts for textual display of the instrument procedure informationwithin the vertical profile as shown in FIG. 3.

In an exemplary embodiment, the aircraft procedure display process 200continues by determining the horizontal scale for the navigationalsegments of the vertical profile (task 214). The horizontal scale shouldbe understood as the ratio of a horizontal unit of distance on thedisplay device (e.g., moving one pixel horizontally or one column ofpixels) to the equivalent distance on the ground. In an exemplaryembodiment, the aircraft procedure display process 200 determines thehorizontal scale for each navigational segment based on the allocatedhorizontal dimensions for the respective segment and the distanceassociated with the respective segment. In this regard, because theallocated horizontal dimensions and/or the distances associated witheach respective segment may vary for each navigational segment, theresulting horizontal scale for the vertical profile may be nonuniform.For example, FIG. 3 depicts a piecewise linear allocation of pixelsamong the navigational segments 310, 312, 314, 316 wherein eachnavigational segment 310, 312, 314, 316 comprises the same horizontaldimensions, that is, the same number of columns of pixels are allocatedto each navigational segment 310, 312, 314, 316. However, the distancesassociated with the individual navigational segments 310, 312, 314, 316vary. As shown, the first navigational segment 310 has an associateddistance of two nautical miles, while the second and third navigationalsegments 312, 314 have associated distances greater than five nauticalmiles each, and the fourth navigational segment 316 has an associateddistance of only half of a nautical mile. As a result, the ratio ofhorizontal dimensions to distance varies for each segment. For example,one pixel horizontally within the second navigational segment 312corresponds to a greater horizontal distance on the ground than onepixel horizontally within the other segments 310, 314, 316. In otherwords, the horizontal scales for the navigational segments 310, 312,314, 316 are not equal, resulting in a nonuniform horizontal scale forthe vertical profile 308.

In an exemplary embodiment, the aircraft procedure display process 200continues by displaying and/or rendering the segments of the verticalprofile on the display device based on the allocated display dimensions(task 216). For example, in the illustrated embodiment of FIG. 3, eachsegment 310, 312, 314, 316, 318, 320 are displayed and/or rendered withthe same vertical dimension (i.e., each segment 310, 312, 314, 316, 318,320 is allocated and occupies the same number of rows of pixels), whilethe navigational segments 310, 312, 314, 316 are displayed and/orrendered with the same (or equal) horizontal dimension (i.e., piecewiselinear allocation of columns of pixels among the navigational segments310, 312, 314, 316).

In an exemplary embodiment, the aircraft procedure display process 200also displays and/or renders the navigational information and/orinstrument procedure information within the vertical profile. Forexample, as shown in FIG. 3, the navigational reference points 311, 313,315, 317 that represent boundaries for the navigational segments 310,312, 314, 316 may be rendered and/or displayed on the vertical profile308. In addition, the instrument procedure information and/or othernavigational information for the individual segments are displayedand/or rendered within the respective segment. For example, as shown inFIG. 3, the ground distance corresponding to the first navigationalsegment 310 (e.g., two nautical miles of the distance between referencepoints 311, 313) and the altitude minimum (e.g., 8,500 feet) are bothdisplayed and/or rendered within the first navigational segment 310.Likewise, the ground distances corresponding to the other navigationalsegments 312, 314, 316 and the altitude minima are also displayed and/orrendered within the respective navigational segment 312, 314, 316. Inaddition, the aircraft procedure display process 200 may displaypre-approach information within the pre-approach segment 320 and theaircraft procedure display process 200 may also display and/or render agraphical representation of the landing location 322 (e.g., a runway atairport 306) along with the elevation of the landing location 322 withinthe runway segment 318.

In an exemplary embodiment, the aircraft procedure display process 200displays and/or renders a graphical representation of the altitudecriteria for the plurality of segments based on the vertical scale forthe vertical profile. In this regard, the aircraft procedure displayprocess 200 may display and/or render a horizontal line within arespective segment that is positioned vertically within the respectivesegment based on the uniform vertical scale such that the linecorresponds to the altitude criterion (e.g., the minimum descentaltitude) for the respective segment. For example, as shown in FIG. 3,the aircraft procedure display process 200 may display and/or render ahorizontal line 324 within the first navigational segment 310 thatcorresponds to the minimum descent altitude associated with the firstnavigational segment 310 (e.g., 8,500 feet), wherein the horizontal line324 is positioned vertically based on the uniform vertical scale. In asimilar manner, the aircraft procedure display process 200 displaysand/or renders a horizontal line 326 within the second navigationalsegment 312 that corresponds to the minimum descent altitude (e.g.,6,401 feet) associated with the second navigational segment 312 and ahorizontal line 328 within the third navigational segment 314 thatcorresponds to the minimum descent altitude (e.g., 5,500 feet)associated with the third navigational segment 314. In this manner,instrument procedure information and/or navigational information relatedto altitude (e.g., altitude minimums) is displayed and/or rendered basedon the uniform vertical scale for the vertical profile.

In an exemplary embodiment, the aircraft procedure display process 200displays and/or renders a profile view of the flight path (e.g., anapproach course or departure course) for the identified aircraft actionon the vertical profile based on the uniform vertical scale and thenonuniform horizontal scale. In this regard, the profile view of theflight path consists of a plurality of line segments connecting theminimum descent altitudes across the navigational segments correspondingto the altitude minimums at each navigational reference point. Forexample, as shown in FIG. 3, the profile view of the approach course 307consists of a first line segment 330 from the pre-approach altitudeminimum (e.g., 9,000 feet) at the border of the pre-approach segment 310and the first navigational segment 310 (i.e., the minimum altitude atthe first navigational reference point 311) to the altitude minimumassociated with the first navigational segment 310 (e.g., 8,500 feet) atthe border with the second navigational segment 312. A second linesegment 332 of the profile view of the approach course 307 connects fromthe altitude minimum for the first navigational segment 310 at theborder with the second navigational segment 312 (i.e., the minimumaltitude at the second navigational reference point 313) to the altitudeminimum associated with the second navigational segment 312 (e.g., 6,401feet) at the border of the third navigational segment 314. A third linesegment 334 of the approach course connects from the altitude minimumfor the second navigational segment 312 at the border with the thirdnavigational segment 314 (i.e., the minimum altitude at the thirdnavigational reference point 315) to the altitude minimum for the thirdnavigational segment 314 (e.g., 5,500 feet) at the border of the fourthnavigational segment 316. As shown, the final line segment 336 of theprofile view of the approach course 307 connects from the altitudeminimum for the third navigational segment 314 at the border with thefourth navigational segment 316 (i.e., the minimum altitude at thefourth navigational reference point 317) to the missed approach point338 (MAP). In alternative embodiments, instead of ending at the missedapproach point 338, the final line segment 336 may continue to thelanding location 322. As a result, a profile view of the approach course307 is displayed in the vertical profile 308 in a manner that isinfluenced by the uniform vertical scale and nonuniform horizontalscale.

In an exemplary embodiment, the aircraft procedure display process 200continues by displaying and/or rendering a graphical representation ofterrain associated with the vertical profile, that is, the terrainunderlying the approach course for the respective segments of theapproach (task 218). The aircraft procedure display process 200 rendersand/or displays the graphical representation of the terrain within thevertical profile in a manner that is influenced by the uniform verticalscale and nonuniform horizontal scale of the vertical profile, that is,the vertical features and/or elevation of the terrain are displayedand/or rendered in accordance with the uniform fixed vertical scalewhile the horizontal cross-sectional view of the terrain is renderedand/or displayed in accordance with the horizontal scale of theindividual segments (i.e., the nonuniform horizontal scale of thevertical profile). For example, as shown in FIG. 3, the graphicalrepresentation of the terrain 340 within the first navigational segment310 is displayed and/or rendered based on the uniform vertical scale forthe vertical profile 308 and the horizontal scale for the firstnavigational segment 310, the graphical representation of the terrain342 within the second navigational segment 312 is displayed and/orrendered based on the uniform vertical scale and the horizontal scalefor the second navigational segment 312, the graphical representation ofthe terrain 344 within the third navigational segment 314 is displayedand/or rendered based on the uniform vertical scale and the horizontalscale for the third navigational segment 314, and so on. In this manner,the terrain underlying the approach course 307 for the plurality ofsegments is rendered on the vertical profile 308 in a manner thataccurately reflects the relationship of the real-world terrain relativeto the altitude minima and the distances associated with the individualsegments.

In an exemplary embodiment, the aircraft procedure display process 200continues by displaying and/or rendering a graphical representation ofthe aircraft within the vertical profile in accordance with the uniformvertical scale and the nonuniform horizontal scale (task 220). In anexemplary embodiment, the aircraft procedure display process 200 obtainsthe instantaneous position of the aircraft and displays and/or renders agraphical representation of the aircraft within the segmentcorresponding to the aircraft's position. For example, as shown in thenavigational map 300 of FIG. 3, the aircraft 302 has just traversed theTAKLE intersection, indicating that the aircraft 302 is within thesecond navigational segment 312. As shown, a second graphicalrepresentation of the aircraft 346 is rendered and/or displayed in thevertical profile 308 within the second navigational segment 312. In anexemplary embodiment, the aircraft 346 is positioned vertically withinthe navigational segment 312 based on the fixed vertical scale such thatit corresponds to the instantaneous altitude of the aircraft. As shown,the instantaneous altitude (e.g., 8,000 feet) may also be displayedand/or rendered in a textual format proximate the aircraft symbology346. The aircraft 346 is positioned horizontally within the secondnavigational segment 312 based on the horizontal scale for thenavigational segment 312 such that the position of the aircraft 346 withrespect to the segment boundaries corresponds to the relative real-worldposition of the aircraft between the two reference points 313, 315 thatdefine the segment 312. In this manner, the aircraft 346 is verticallyand horizontally positioned with respect to the terrain 342 within thenavigational segment 312 in a manner that reflects the relativereal-world positioning of the aircraft with respect to the underlyingreal-world terrain. The aircraft procedure display process 200 maycontinue to update the positioning of the aircraft 346 within thevertical profile 308 (and the positioning of the aircraft 302 on thenavigational map 300) as the aircraft travels.

In accordance with one embodiment, the aircraft procedure displayprocess 200 continues by determining whether the vertical profile shouldbe updated (task 222). In this regard, if the aircraft procedure displayprocess 200 determines and/or identifies that one of the more segmentson the vertical profile are no longer relevant, for example, if theaircraft has already traversed through one or more segments of thevertical profile, the aircraft procedure display process 200 mayreallocate the display dimensions of the vertical profile among theremaining segments in a similar manner as described above (task 210).For example, referring now to FIG. 3 and FIG. 4, in response toidentifying and/or determining the instantaneous location of theaircraft is within the second navigational segment 312, the aircraftprocedure display process 200 may update the vertical profile 308 byremoving the pre-approach segment 320 and first navigational segment 310and reallocating the display dimensions for the vertical profile 308among the remaining relevant segments 312, 314, 316, 318 resulting inthe vertical profile 408 overlying the bottom portion of thenavigational map 400 of FIG. 4. For example, as shown in FIG. 4, thedisplay dimensions have been reallocated in a piecewise linear manneracross the remaining navigational segments 412, 414, 416. The aircraftprocedure display process 200 may determine an updated vertical and/orhorizontal scale for the vertical profile 408 and display the remainingsegments 412, 414, 416, 418 in a similar manner as set forth above(tasks 212, 214, 216). In this manner, navigational segments 412, 414,416 are allocated updated horizontal dimensions, resulting in an updatedhorizontal scale for each of the navigational segments 412, 414, 416.The vertical scale and/or horizontal scale for the vertical profile 408may or may not be different from the vertical scale and/or horizontalscale for the previously displayed vertical profile 308, however, thevertical profile 408 retains the characteristic of a uniform verticalscale across segments. In this manner, the nonuniform horizontal scalemay be dynamically updated based on the instantaneous position of theaircraft. The aircraft procedure display process 200 continues bydisplaying the terrain and the aircraft within the updated verticalprofile 408 in a similar manner as set forth above (tasks 218, 220). Theloop defined by tasks 210, 212, 214, 216, 218, 220 may repeat as desiredto dynamically update the vertical profile until the aircraft hascompleted the identified aircraft action.

One advantage of the systems and/or methods described above is that thevertical profile for an approach (or departure) may be displayed and/orrendered in a manner that accurately reflects the relative real-worldposition of the aircraft with respect to the terrain and/or airportwithin a limited display area. The vertical profile is displayed and/orrendered with a nonuniform horizontal scale which allows the entirevertical profile to be displayed and/or rendered within the availabledisplay area regardless of the length of the navigational segments thatcomprise the approach. The vertical profile is also displayed and/orrendered with a fixed uniform vertical scale based on the altitudeminimums and the amount of available display area. As a result, theterrain associated with the approach may be displayed and/or renderedwithin the vertical profile based on the nonuniform horizontal scale andthe fixed uniform vertical scale such that the graphical representationof the terrain accurately reflects the relative real-world positioningof the terrain with respect tot eh airport. A graphical representationof the aircraft may also be displayed within the vertical profile basedon the nonuniform horizontal scale and the fixed uniform vertical scale.In this manner, the limited available display area is utilized to allowa user, such as a pilot or co-pilot, to quickly and intuitivelyascertain the relative real-world positioning of the aircraft withrespect to the approach course, the airport, the navigational referencepoints, the minimum descent altitude, and the underlying terrain. Thevertical profile is positioned with respect to a navigational map orother displayed content in a manner that allows the user to maintainsituational awareness while simultaneously reviewing the instrumentprocedure information associated with the vertical profile.

While at least one exemplary embodiment has been presented in theforegoing detailed description, it should be appreciated that a vastnumber of variations exist. It should also be appreciated that theexemplary embodiment or exemplary embodiments are only examples, and arenot intended to limit the scope, applicability, or configuration of thesubject matter in any way. Rather, the foregoing detailed descriptionwill provide those skilled in the art with a convenient road map forimplementing an exemplary embodiment of the subject matter. It beingunderstood that various changes may be made in the function andarrangement of elements described in an exemplary embodiment withoutdeparting from the scope of the subject matter as set forth in theappended claims.

1. A method for presenting procedure information for a vertical profilecomprising a plurality of segments between a first navigationalreference point and a second navigational reference point on a displaydevice associated with an aircraft, the method comprising: displaying afirst segment of the plurality of segments with a vertical scale and afirst horizontal scale, the first horizontal scale being based on afirst distance associated with the first segment; and displaying asecond segment of the plurality of segments with the vertical scale anda second horizontal scale, the second horizontal scale being based on asecond distance associated with the second segment, wherein the firsthorizontal scale and the second horizontal scale are not equal.
 2. Themethod of claim 1, further comprising: displaying a first graphicalrepresentation of terrain within the first segment, wherein the firstgraphical representation of terrain is displayed based on the verticalscale and the first horizontal scale; and displaying a second graphicalrepresentation of terrain within the second segment, wherein the secondgraphical representation of terrain is displayed based on the verticalscale and the second horizontal scale.
 3. The method of claim 1, furthercomprising displaying a graphical representation of the aircraft on thedisplay device within the first segment, wherein the graphicalrepresentation of the aircraft is positioned based on the vertical scaleand the first horizontal scale such that the graphical representation ofthe aircraft accurately reflects an instantaneous position of theaircraft.
 4. The method of claim 1, further comprising: allocating firsthorizontal dimensions to the first segment, the first horizontal scalebeing equal to a ratio of the first horizontal dimensions to the firstdistance; and allocating second horizontal dimensions to the secondsegment, the second horizontal scale being equal to a ratio of thesecond horizontal dimensions to the second distance.
 5. The method ofclaim 4, wherein: allocating first horizontal dimensions to the firstsegment comprises allocating a first number of columns of pixels to thefirst segment, the first horizontal scale being equal to the firstnumber divided by the first distance; and allocating second horizontaldimensions to the second segment comprises allocating a second number ofcolumns of pixels to the second segment, the second horizontal scalebeing equal to the second number divided by the second distance.
 6. Themethod of claim 5, the first distance and the second distance beingunequal, wherein allocating second horizontal dimensions to the secondsegment comprises allocating the second number of columns of pixels tothe second segment, the second number being equal to the first number.7. The method of claim 1, further comprising: displaying the firstdistance within the first segment; and displaying the second distancewithin the second segment.
 8. The method of claim 1, further comprisingdisplaying a graphical representation of a flight path for an approachon the display device within the vertical profile, wherein the graphicalrepresentation of the flight path is influenced by the vertical scale,the first horizontal scale, and the second horizontal scale.
 9. A methodfor presenting procedure information for an aircraft action between afirst navigational reference point and a second navigational referencepoint on a display device associated with an aircraft, the methodcomprising: rendering a vertical profile for the aircraft action on thedisplay device, wherein the vertical profile is rendered with a uniformvertical scale and a nonuniform horizontal scale; and rendering agraphical representation of the aircraft on the display device withinthe vertical profile, wherein the graphical representation of theaircraft is positioned within the vertical profile based on thenonuniform horizontal scale and the uniform vertical scale such that thegraphical representation of the aircraft accurately reflects aninstantaneous position of the aircraft.
 10. The method of claim 9, thevertical profile including a plurality of navigational segments, whereinrendering the vertical profile with the nonuniform horizontal scalecomprises: allocating equal horizontal dimensions to a firstnavigational segment of the plurality of navigational segments and asecond navigational segment of the plurality of navigational segments;rendering the first navigational segment with the uniform vertical scaleand a first horizontal scale; and rendering the second navigationalsegment of the plurality of navigational segments with the uniformvertical scale and a second horizontal scale, wherein the firsthorizontal scale and the second horizontal scale are not equal.
 11. Themethod of claim 10, further comprising: determining the first horizontalscale based on a first distance associated with the first navigationalsegment and the allocated horizontal dimensions; and determining thesecond horizontal scale based on a second distance associated with thesecond navigational segment and the allocated horizontal dimensions,wherein the first distance and the second distance are unequal.
 12. Themethod of claim 10, wherein rendering the graphical representation ofthe aircraft comprises rendering the graphical representation of theaircraft on the display device within the first navigational segment,wherein the graphical representation of the aircraft is positionedwithin the first navigational segment based on the first horizontalscale and the uniform vertical scale such that the graphicalrepresentation of the aircraft accurately reflects the instantaneousposition of the aircraft.
 13. The method of claim 10, furthercomprising: rendering a first graphical representation of terrain withinthe first navigational segment, wherein the first graphicalrepresentation of terrain is rendered based on the uniform verticalscale and the first horizontal scale; and rendering a second graphicalrepresentation of terrain within the second navigational segment,wherein the second graphical representation of terrain is rendered basedon the uniform vertical scale and the second horizontal scale.
 14. Themethod of claim 9, further comprising updating the nonuniform horizontalscale based on the instantaneous position of the aircraft.
 15. Themethod of claim 9, further comprising rendering a graphicalrepresentation of terrain on the display device within the verticalprofile, wherein the graphical representation of terrain is renderedbased on the uniform vertical scale and the nonuniform horizontal scalesuch that the positioning of the graphical representation of theaircraft with respect to the graphical representation of terrainaccurately reflects the instantaneous position of the aircraft withrespect to the terrain.
 16. The method of claim 9, further comprisingrendering a graphical representation of a flight path for the aircraftaction on the display device within the vertical profile, wherein thegraphical representation of the flight path is displayed based on theuniform vertical scale and the nonuniform horizontal scale.
 17. Adisplay system onboard an aircraft comprising a display device havingrendered thereon: a navigational map; and a vertical profile for anapproach with a uniform vertical scale comprising: a first navigationalsegment having a first horizontal scale being based on a first distanceassociated with the first navigational segment; and a secondnavigational segment having a second horizontal scale based on a seconddistance associated with the second navigational segment, wherein thefirst horizontal scale and the second horizontal scale are not equal.18. The display system of claim 17, wherein the first navigationalsegment and the second navigational segment are allocated displaydimensions within a viewing area on the display device such that ahorizontal dimension of the first navigational segment is equal to ahorizontal dimension of the second navigational segment, wherein thefirst horizontal scale is equal to a ratio of the horizontal dimensionof the first navigational segment to the first distance and the secondhorizontal scale is equal to a ratio of the horizontal dimension of thesecond navigational segment to the second distance.
 19. The displaysystem of claim 17, wherein the vertical profile further comprises: afirst graphical representation of terrain corresponding to the firstnavigational segment, wherein the first graphical representation ofterrain is rendered within the first navigational segment based on theuniform vertical scale and the first horizontal scale; and a secondgraphical representation of terrain corresponding to the secondnavigational segment, wherein the second graphical representation ofterrain is rendered within the second navigational segment based on theuniform vertical scale and the second horizontal scale.
 20. The displaysystem of claim 17, wherein the vertical profile further comprises agraphical representation of the aircraft within the first navigationalsegment based on an instantaneous position of the aircraft correspondingto the first navigational segment, wherein the graphical representationof the aircraft is positioned within the first navigational segmentbased on the uniform vertical scale and the first horizontal scale.